diff --git a/src/chapter2/part2/MyLinkedList.py b/src/chapter2/part2/MyLinkedList.py
index a0d2fe4..1bbffb7 100644
--- a/src/chapter2/part2/MyLinkedList.py
+++ b/src/chapter2/part2/MyLinkedList.py
@@ -49,6 +49,8 @@ def remove(self, index):
             # 删除头节点
             removed_node = self.head
             self.head = self.head.next
+            if self.size == 1:
+                self.last == Node
         elif index == self.size - 1:
             # 删除尾节点
             prev_node = self.get(index-1)
diff --git a/src/chapter5/part9/RemoveKDigits.py b/src/chapter5/part9/RemoveKDigits.py
index 390fcab..377e8f3 100644
--- a/src/chapter5/part9/RemoveKDigits.py
+++ b/src/chapter5/part9/RemoveKDigits.py
@@ -44,14 +44,12 @@ def remove_k_digits_v2(num, k):
         # 遍历到的当前数字入栈
         stack.append(c)
     # 用栈构建新的整数字符串
-    if new_length <= 0:
-        return "0"
-    return "".join(stack)
+    return "".join(stack[:new_length])
 
 
-print(remove_k_digits("1593212", 3))
-print(remove_k_digits("30200", 1))
-print(remove_k_digits("10", 2))
-print(remove_k_digits("541270936", 3))
-print(remove_k_digits("1593212", 4))
-print(remove_k_digits("10000100002", 2))
+print(remove_k_digits_v2("123456789", 3))
+print(remove_k_digits_v2("30200", 1))
+print(remove_k_digits_v2("10", 2))
+print(remove_k_digits_v2("541270936", 3))
+print(remove_k_digits_v2("1593212", 4))
+print(remove_k_digits_v2("10000100002", 2))